Publication Date

8-27-2020

Document Type

Article

Disciplines

Higher Education | Physics | Science and Mathematics Education

Publication Title

Physical Review Physics Education Research

Volume

16

Issue

2

Digital Object Identifier

10.1103/PhysRevPhysEducRes.16.020114

Abstract

In deciding on a student’s grade in a class, an instructor generally needs to combine many individual grading judgments into one overall judgment. Two relatively common numerical scales used to specify individual grades are the 4-point scale (where each whole number 0–4 corresponds to a letter grade) and the percent scale (where letter grades A through D are uniformly distributed in the top 40% of the scale). This paper uses grading data from a single series of courses offered over a period of 10 years to show that the grade distributions emerging from these two grade scales differed in many ways from each other. Evidence suggests that the differences are due more to the grade scale than to either the students or the instructors. One major difference is that the fraction of students given grades less than C− was over 5 times larger when instructors used the percent scale. The fact that each instructor who used both grade scales gave more than 4 times as many of these low grades under percent scale grading suggests that the effect is due to the grade scale rather than the instructor. When the percent scale was first introduced in these courses in 2006, one of the authors of this paper, who is also one of the instructors in this dataset, had confidently predicted that any changes in course grading would be negligible. They were not negligible, even for this instructor.

Keywords

Educational policy, Instructional strategies, Physics education research

Comments

This article was published in Physical Review Physics Education Research, volume 16, issue 2, 2020 and can also be found online at this link https://doi.org/10.1103/PhysRevPhysEducRes.16.020114. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

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